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Effective Current calculation

I am reviewing plans for a floating marina project and need some clarification. The drawings provide a chart for the power pedestal branch circuit calculations that seems to use "effective current" to size overcurrent protection. To be brief, an example single phase 120/240v circuit has a load of 270 amps (9 x 30a receptacles). After the adjustments from NEC 555.12 (80% load factor & 90% meter factor) I arrive at 194.4 amps. The chart lists an effective current of 108 amps and a 125 amp circuit breaker. I am questioning the effective current. Is the value correct? And should that be used here?

Sorry, just getting back to this now. Thanks for all the input. I was trying to attach part of the chart that I was referring to but was having difficulty. Let me elaborate a bit. I stopped just short of calculating the "effective current" (at 194.4a) in my original question. My understanding is that the calculation for "effective current" is I/sqrt(2). If that's correct, eff. current would be 137.5 amps. The person creating this chart would be way off with the 108a. Also, proving the chart further, I find that the "meter factor" of 90% was only used sometimes. Actually, if you drop the meter factor in the example I provided and just use 270a x 0.8 = 216a, it looks like he divided the current by (2), arriving at 108a, and not the square root of (2). I don't know for sure but there are (14) circuits and the pattern is the same. I am just trying to understand this chart before pointing-out any discrepancies. Does this help at all?

The wording "effective" current is usually used in a classroom setting to try to have a student understand that for a particular AC waveform that a simple multiplier can be used to relate that AC waveform to a DC current based on having the same heating effect in a resistor. As the AC waveform changes that multiplier changes. For a sine wave a ratio is Ipeak * 0.707 = Irms. Theoretically one can calculate this ratio with calculus. The 0.707 value is an approximation of the exact value of sq-root of 2 divided by 2.

In general I would use the words "effective" and RMS as being identical.

If you have a split phase system based on a center tapped 240 V secondary, your loads are 120 V, and you try to approximately balance the loads on you source, then one phase is loaded to 4*30 A and the other to 5*30 A. So you would use an RMS load current of 150 A. The 150 is the greater of the two split loads and will determine breaker and wire sizes.